rb-json-hot — measured, still hint
Status
hint. Wall-clock JSONL: rb-json-hot.jsonl. Not corpus-triaged. The 2026-10-22 corpus verdict does not cover this slug.
Measurement
20000 parses of one fixed JSON object. After parses once. A changing payload cannot use this after shape.
| role | case | median_ms | ops | ratio |
|---|---|---|---|---|
| after | parse_once | 0.781000 | 20000 | 1 |
| before | parse_each_iter | 6.116000 | 20000 | 7.831 |
Ruby 4.0.8, 2026-10-23. Warm 3, median of 9.
The microbench shows a cost for this one shape. Default stays hint until the shape is corpus-triaged. This ratio is not a general speedup.
Unblock
Do not set the default to error from this file alone. A changing input, a cold path, or another ABI can erase the difference. Corpus triage is still required before any default change.